The field of the invention relates generally to fuel leakage prevention, and more particularly to a method and a fuel accumulator system for preventing fuel leakage in a gas turbine engine.
Aircraft turbofan engines produce a high amount of heat in order to meet a stringent requirement on fuel efficiency and pollutants. During shutdown of these engines, the engine heat flows to cooler sections of the engine, which may be referred to as soakback. Soakback can cause the fuel manifold, which is cooler than other parts of the engine, to increase in temperature. The fuel manifold is a closed system at engine shutdown, so as the temperature rises, fuel pressure increases because of bulk fuel expansion. If the pressure rises above the cracking pressure of the fuel nozzles, then the fuel will leak into the hot engine, causing fuel vapors to leak out of both the inlet and the exhaust of the engine. The vapors can affect aircraft certification and customer acceptance, as well as increase the costs associated with operating the engine.
Designing a ventilation system to enable the heat to escape typically requires long lead times and difficult integration with the engine, both of which increase costs of implementing ventilation systems. Accordingly, a system is needed for these engines that prevents pressure build-up in the fuel manifold, thereby preventing fuel from leaking into the engine.